Cache the VRG retrieved from S3 store to improve retrieval efficiency

Signed-off-by: Benamar Mekhissi <bmekhiss@ibm.com>

controllers/drplacementcontrol.go

@@ -64,7 +64,8 @@ type DRPCInstance struct {
 	mcvRequestInProgress bool
 	volSyncDisabled      bool
 	userPlacement        client.Object
-	vrgs                 map[string]*rmn.VolumeReplicationGroup // Populated using MCV
+	vrgsFromMCV          map[string]*rmn.VolumeReplicationGroup // Populated using MCV
+	vrgFromS3            *rmn.VolumeReplicationGroup            // Cache the vrg from s3 if found
 	vrgNamespace         string
 	ramenConfig          *rmn.RamenConfig
 	mwu                  rmnutil.MWUtil
@@ -282,7 +283,7 @@ func (d *DRPCInstance) getCachedVRG(clusterName string) *rmn.VolumeReplicationGr
 // inaccessible or not represented in the MCV data.
 //
 // The function performs the following steps:
-//  1. Iterates over all managed clusters and tries to find their corresponding VRGs in `d.vrgs`.
+//  1. Iterates over all managed clusters and tries to find their corresponding VRGs in `d.vrgsFromMCV`.
 //     If found, it adds them to the `vrgs` map and checks if any VRG is marked as primary.
 //  2. If the number of retrieved VRGs matches the number of DR clusters, it returns the `vrgs` map immediately
 //     as a shortcut, indicating that all required VRGs have been collected.
@@ -298,7 +299,7 @@ func (d *DRPCInstance) fetchVRGsFromMClusterOrS3() map[string]*rmn.VolumeReplica
 	var primaryFound bool
 
 	for _, drCluster := range d.drClusters {
-		vrg, found := d.vrgs[drCluster.Name]
+		vrg, found := d.vrgsFromMCV[drCluster.Name]
 		if !found {
 			continue
 		}
@@ -317,15 +318,12 @@ func (d *DRPCInstance) fetchVRGsFromMClusterOrS3() map[string]*rmn.VolumeReplica
 
 	// If MCV didn't return a primary VRG, then we need to get it from the s3 store.
 	if !primaryFound {
-		vrg := GetLastKnownVRGPrimaryFromS3(d.ctx, d.reconciler.APIReader,
-			AvailableS3Profiles(d.drClusters), d.instance.GetName(),
-			d.vrgNamespace, d.reconciler.ObjStoreGetter, d.log)
-		if vrg != nil {
-			primaryCluster := vrg.GetAnnotations()[DestinationClusterAnnotationKey]
+		if d.vrgFromS3 != nil {
+			primaryCluster := d.vrgFromS3.GetAnnotations()[DestinationClusterAnnotationKey]
 			// Double check that we don't have already an entry in the vrgs populated using MCV
-			_, found := d.vrgs[primaryCluster]
+			_, found := d.vrgsFromMCV[primaryCluster]
 			if !found {
-				vrgs[primaryCluster] = vrg
+				vrgs[primaryCluster] = d.vrgFromS3
 			}
 		}
 	}

controllers/drplacementcontrol_controller.go

@@ -939,11 +939,14 @@ func (r *DRPlacementControlReconciler) createDRPCInstance(
 		return nil, err
 	}
 
-	vrgs, _, _, err := getVRGsFromManagedClusters(r.MCVGetter, drpc, drClusters, vrgNamespace, log)
+	vrgsFromMCV, _, _, err := getVRGsFromManagedClusters(r.MCVGetter, drpc, drClusters, vrgNamespace, log)
 	if err != nil {
 		return nil, err
 	}
 
+	vrgFromS3 := GetLastKnownVRGPrimaryFromS3(ctx, r.APIReader,
+		AvailableS3Profiles(drClusters), drpc.GetName(), vrgNamespace, r.ObjStoreGetter, log)
+
 	d := &DRPCInstance{
 		reconciler:      r,
 		ctx:             ctx,
@@ -952,7 +955,8 @@ func (r *DRPlacementControlReconciler) createDRPCInstance(
 		userPlacement:   placementObj,
 		drPolicy:        drPolicy,
 		drClusters:      drClusters,
-		vrgs:            vrgs,
+		vrgsFromMCV:     vrgsFromMCV,
+		vrgFromS3:       vrgFromS3,
 		vrgNamespace:    vrgNamespace,
 		volSyncDisabled: ramenConfig.VolSync.Disabled,
 		ramenConfig:     ramenConfig,
@@ -1025,7 +1029,7 @@ func (r *DRPlacementControlReconciler) reconcileDRPCInstance(d *DRPCInstance, lo
 		beforeProcessing = *d.instance.Status.LastUpdateTime
 	}
 
-	if !ensureVRGsManagedByDRPC(d.log, d.mwu, d.vrgs, d.instance, d.vrgNamespace) {
+	if !ensureVRGsManagedByDRPC(d.log, d.mwu, d.vrgsFromMCV, d.instance, d.vrgNamespace) {
 		log.Info("Requeing... VRG adoption in progress")
 
 		return ctrl.Result{Requeue: true}, nil
@@ -2936,3 +2940,4 @@ func (r *DRPlacementControlReconciler) drpcHaveCommonClusters(ctx context.Contex
 
 	return drpolicyClusters.Intersection(otherDrpolicyClusters).Len() > 0, nil
 }
+